Doctors at The Methodist Hospital are experimenting with a new treatment for the diseased or injured pancreas in which they remove the organ and implant its insulin-producing cells in the patient's arm or leg.

The research, conducted on the first patient a month ago, is part of an ongoing inquiry into how best to prevent diabetes in a person whose pancreas has been removed because of pancreatitis, trauma, or benign or early-stage malignant tumors.

The work could also speed up national efforts to use stem cells, the building blocks of tissue, to cure Type 1 and Type 2 diabetes.

"We're very early in the process, but I'm confident this work is going to prove effective," said Dr. Craig Fischer, a surgeon at Methodist and leader of the research. "It may sound wild to the layperson, but it's actually very logical."

The patient involved in the transplant research, Wanda Prouty, is the first person in North America to receive islets in an arm or leg, following a small study of such transplants in Sweden. The most conventional technique is to put islets in the liver, though that has limitations.

Most Popular

The procedure involves isolating the removed pancreas' islets, groups of cells that produce the insulin necessary to balance sugar levels in the blood. The islets are enhanced in a laboratory and reimplanted so the patient will continue manufacturing his or her own insulin.

Without the procedure, patients having their pancreases removed become diabetic and require insulin shots. A quarter of such patients die within five years, and the rest usually deal with particularly burdensome diabetes.

Although the research's immediate aim is limited — it would benefit about 30 percent of patients undergoing the roughly 4,000 operations performed yearly to remove the pancreas — it would be huge if it some day can be applied to all of the nearly 24 million people in the United States with some form of diabetes.

Early results promising

Prouty suffered from chronic pancreatitis: long-standing inflammation of the pancreas that causes persistent pain and can be fatal. Although a conclusive verdict can't be made for at least five months, Fischer said blood tests show the islets have lodged in muscle in Prouty's forearm and are producing insulin.

Downplaying the novelty of having the equivalent of a pancreas in her arm, Prouty said last week she never thinks about the location. She said the possibility she might regain a normal life after the past few years of constant, sometimes excruciating, pain is "a miracle."

"If putting it in the arm is what it takes, that's fine with me," said Prouty, a 55-year-old from Texas City. "Chronic pancreatitis is like a death sentence, and there's a lot of stuff I still want to do."

Islet transplantation dates back two decades. In the early 1990s, the procedure involved taking islets from the pancreases of cadavers and transplanting them into the livers of diabetics. Such donor cells get the same reception as any other foreign invader — the immune system attacks them.

That's not the case with islet transfusions from the patient's own pancreas, which have been done for about a decade. So far, islet transplantations seem to work best in the liver — 60 percent to 70 percent of such patients produce all the insulin they need — presumably because the liver is a great source of the blood the islets need.

But the liver isn't necessarily the best host. For one, such a procedure is not recommended for patients with liver function abnormalities or for pancreatic cancer patients.

For another, pancreas removal and liver implantation make for a 12-hour, two-part surgery that is risky and taxing. Serious complications, including death, have occurred.

But the search for alternate sites hasn't been easy. Attempts to implant the islets in the kidney, the lower abdomen and the bloodstream all failed.

However, recent arm implants at the Karolinska Institute just outside Stockholm intrigued Fischer, who wondered why no one had thought of the idea earlier. Nine patients had the islets implanted in their arms, and each ended up producing insulin. If the experiment can be duplicated, Fischer figured, the technique would be safer and simpler than implants in the liver, with the second part of the dual surgery able to be done under local anesthesia.

Not everyone is convinced.

"I'm a little skeptical because in animal models nothing worked as well as the liver," said Dr. David Sutherland, a transplant surgeon at the University of Minnesota and the pioneer of implanting patient islets in the liver. "But it's important to try lots of sites so we have data about exactly what the best options are."

To that end, Methodist's trial calls for the islets to be implanted over the next five years in either the arm or leg of about 30 patients whose livers aren't good candidates.

The effort is possible because of Methodist's recently created Islet Transplantation Laboratory, one of about 10 in the nation. There, following surgery to remove the pancreas, the organ is stripped of its islets — a process hospital transplantation director Dr. Osama Gaber compares to "shaking a tree, then separating the fruit from the leaves and branches."

Obstacles remain

Technicians at the lab then purify and process the islets before transplantation. They are working to address the premature die-off of transplanted islets — about half of the 350,000 to 400,000 transferred in a single procedure don't survive — by encapsulating them with a built-in oxygen supply that'll keep them alive in the body until blood can nourish them.

Fischer said the research will culminate in efforts to apply the lessons learned to all diabetics. Because the lab has access to hard-to-come-by human islet cells, it will be in the forefront of national efforts to morph stem cells into islets. Once that is achieved, researchers could clone the islets and doctors could implant them in sites shown to be hospitable, allowing Type 1 diabetics to produce their own insulin and Type 2 diabetics to use theirs properly.

Fischer said he's confident such advances are on the horizon. But he admits there are significant hurdles ahead.

"Just about islet cell transplantation, there's a lot to learn," Fischer said. "What are the optimal ways to grow islets? How can we create a different kind of pancreas in someone's arm? What are the advantages and disadvantages?

Now Playing:

"But as we work out these questions in the next few years," he said, "we're going to be a lot closer to routinely preventing diabetes in patients having their pancreas removed. Then, in the next decade, I hope we can close in on cloned islets that can treat or even cure diabetes."